In my book, Your Church Is Too Small, I argue that sectarianism is almost always found where disunity abounds among Christians. This is not a novel argument but one that Christians in general, and conservative Christians in particular, do not see clearly enough. We are far more sectarian than we generally think when we consider our own views and actions.
The word sectarianism comes from the Latin word secta, which means a faction or party. It comes from the word sequi, which meant “to follow.” Generally sectarians follow a sect leader, or leaders, of some type. The word sect generally referred, in church history, to a group that broke away from a larger group, often in protest over distinct views. If used this broadly the term can refer to almost any religious disagreement. In this absolute sense the earliest Christians were a sect of the Jews.
As I use the term sectarianism it more generally refers to a doctrinaire commitment to one’s own version or views about the church and the faith. It often results in narrow-minded devotion deeply rooted in prejudice and emotion. Those who disagree are condemned, sometimes harshly. In history Christians have killed Christians because of sectarian response. Some sectarians disavow all relationship to an established Christian Church. A correspondingly negative connotation is found in the modern word tribalism.